Support arrangement for a leading-edge high lift device with a fluid duct

This application claims the benefit of European Patent Application Number 22179331.8 filed on Jun. 15, 2022, the entire disclosure of which is incorporated herein by way of reference.

The invention relates to a support arrangement for a leading-edge high-lift device, especially a droop nose device. Further, the invention relates to a leading-edge high-lift system, an aircraft wing and an aircraft equipped with such support arrangement.

For the technical background of the invention, reference is made to the following citations:

Leading-edge high lift systems known from [1] to [4] comprise a leading-edge high lift device such as a leading-edge slat or a Krueger flap or a leading-edge droop nose as well as a support arrangement for movably supporting the leading-edge high lift device to a structure of an aircraft wing.

As defined and known from [1] to [3], a leading-edge droop nose, also called leading edge droop flap or shortly just droop nose, is a device on the leading edge of aircraft wings designed to improve airflow at high pitch angles (high angle of attack). The leading-edge droop nose is similar to the leading-edge slat and the Krueger flap, but with the difference that the entire leading-edge section rotates downwards, whereas the slat and Krueger flap are panels which move away from the wing leading edge when it is deployed.

For avoiding ice accumulation, anti-ice systems are known supplying tempered fluids such as hot air to the interior of a leading-edge section of an aircraft wing, see for example [4]. [4] discloses an anti-ice duct for leading-edge slats wherein the anti-ice duct is configured as a telescopic duct. The telescopic duct is feeding the hot air into the slat, the telescopic duct is following the slat kinematics.

Anti-ice ducts currently used in aircrafts on the market comprise circular and linear telescopic ducts with variable length to follow the movable leading-edge kinematics. The length of the duct is increasing during extension. A spherical joint at the connect to the slat body is accommodating the build tolerances, wing bending, thermal and load displacements.

An object of the invention is to improve a fluid duct to a movable leading-edge high lift device, especially with regard to weight and costs.

For achieving this object, the invention provides a support arrangement according to claim. A leading-edge high lift system, an aircraft wing and an aircraft equipped with such support arrangement are the subject-matters of the further independent claims. Advantageous embodiments are subject-matters of the dependent claims.

According to a first aspect, the invention provides a support arrangement for a leading-edge high lift device comprising a support arm for movably supporting the leading-edge high lift device on a wing structure wherein the support arm is configured as a fluid conduit for feeding fluid to and/or from the leading-edge high lift device.

Preferably, the support arm has a tubular profile and/or is configured as a part of a fluid duct for ducting fluid to and/or from the leading-edge high lift device.

Preferably, the leading-edge high lift device is a leading-edge droop nose device (also called leading edge droop flap, see especially [1] to [3]). Accordingly, the support arrangement is preferably a hinge arrangement for a leading-edge droop nose. Preferably, the support arm is a hinge arm, a first end of the hinge arm having a first rotational joint to be rotatably connected to a structure of a wing, a second end of the hinge arm having a second rotational joint to be rotatably connected to a movable rounded front part of the wing.

Preferably, the hinge arrangement comprises a driving system for driving a rotation of the hinge arm around the first rotational joint.

In accordance with the droop nose kinematic, the hinge arm preferably has a fixed length between the first and second rotational joints. A simple beam with a fluid channel formed therein can be used as hinge arm. The profile section of the hinge arm may have a tubular section, eventually with further outer and/or inner ribs, ridges and/or webs for enhancing stiffness of the arm.

Preferably, the first rotational joint has a circular tube section and a bearing for rotatably supporting the circular tube section, the circular tube section extending transversal to the hinge arm and being fixed to the tubular profile so that the interiors thereof are in fluid communication.

Preferably, the second rotational joint comprises a fluid connection for ducting fluid to a fluid pipe or fluid chamber in the rounded front part.

Preferably, the second rotational joint comprises a link arm controlling an orientation of the rounded front part.

According to another aspect, the invention provides a leading-edge high lift system for an aircraft, comprising a movable leading-edge high lift device supported by a support arrangement according to any of the aforementioned embodiments.

Preferably, the leading-edge high lift device is a droop nose device for an aircraft, comprising a movable rounded front part of a wing including a fluid system wherein the support arrangement is a hinge arrangement for movably connecting the rounded front part to a wing structure and for feeding fluid to and/or from the fluid system.

Preferably, the movable leading-edge high lift device is supported with a plurality of support arms on the wing structure. Most of the support arms may be conventional support arms and one or a part of the support arms may have a tubular profile and/or a fluid channel in order to function as part of a fluid duct.

Preferably, the leading-edge high lift system includes an anti-ice system for distributing tempered fluid along a leading-edge region wherein the tempered fluid is supplied through at least one of the support arms of the support arrangement.

According to a further aspect, the invention provides an aircraft wing having a leading-edge high-lift system according to any of the aforementioned embodiments.

According to another aspect, the invention provides an aircraft having a support arrangement, a leading-edge high-lift system and/or an aircraft wing according to any of the aforementioned embodiments.

Preferred embodiments of the invention have a slat or flap or droop nose support arm that doubles as a fluid conduit for supplying fluid to the leading-edge slat or flap or droop nose.

In some embodiments, the fluid is air and supplied at high pressure and temperature to the slat/flap/droop nose for anti-ice purposes. However, the conduit could also be used to transfer fluids for other purposes e.g., air for flow control purposes in the leading-edge slat/flap/droop nose, etc. In some embodiments, a circular cross section of the conduit is provided, but the cross section of the support arm can be any closed profile as long as it can be supported and loaded as required.

Some embodiments relate to a full span droop nose planform. Especially, some embodiments relate to an integration of a structural anti-ice duct into a full span droop nose configuration.

Some embodiments relate to an implementation of a full span droop nose configuration on future aircrafts. In some embodiments one structural support of one droop nose is combined with the anti-ice duct, which feeds the high lift device with hot air.

In some embodiments one classical hinge arm is changed to a structural anti-ice duct. Preferably, the high-lift device supported by the hinge arm is a leading-edge droop nose device. The kinematics of a droop nose differs from a slat kinematics. Main difference is the location of the hinge point. For the droop nose it is inside the wing profile. Taking the benefit out of this constraint the anti-ice duct length does not need to be increased during deployment and retraction of the droop nose. As well the duct can be structural strengthen to take loads from the device. All attachments on the hinge arm are mounted to the structural duct.

Advantages of preferred embodiments are to reduce the cut outs in the wing fixed leading edge as well as closing elements for the holes in high-speed configuration. Less supporting ribs in the wing fixed leading edge are needed.

shows an aircraftin form of an airplane with an aircraft wingand an enginewith a turbine. In the regionof a leading edgeof the aircraft wing, there is a leading edge high-lift systemincluding a first to fifth leading-edge high lift device.-.and a support arrangementfor movably supporting the high lift devices.-.on a structureof the aircraft wing.

The leading-edge high lift systemcomprises a fluid systemwith a fluid pipeand/or a fluid chamber and/or a fluid distribution system. In the embodiment shown, the fluid systemis an anti-ice systemfor distributing anti-ice fluidsuch as hot pressurized air, e.g., bleed air from the turbine, along at least a part of the leading-edge region. However, the fluid systemmay have (any) other function(s) such as a de-ice system or a fluid control system—e.g., a hydraulic or pneumatic system.

In the preferred embodiment shown, the leading-edge high lift systemis a leading-edge droop nose systemwherein at least a part of the leading-edge high lift devices.-., here the first to fourth high lift device.-., are configured as a droop nose device.-.. The innermost fifth high-lift device.may be configured as a slator as a fifth droop nose device..

Referring now to, the support arrangementis configured to movably support at least one or several of the leading-edge high lift devices.-.on the wing structure. The support arrangementcomprises several support arms.-.movably supporting the leading-edge high lift devices.-.on the wing structure. Each high lift device.-.is supported by two or more of the support arms.-.. As visible from, most of the support arms.-.have a conventional cross section such as a double T cross section as this is known from the droop nose system of the Airbus A350, see [2].

Referring further to, at least one of the support arms.-., here the sixth support arm., is—additionally to its function for movably supporting the associated high-lift device.—configured as a fluid conduit or fluid ductfor feeding fluid to and/or from the leading-edge high lift device.. The sixth support arm.has a tubular profile and is configured as a part of the fluid ductfor ducting fluid to and/or from fluid system. Referring to, the cross section of the sixth support arm.may be a circular tubular section, but also other cross sections are possible as long as a (closed) fluid channelis provided along the support arm.that doubles as a fluid conduit.shows another example for the tubular section formed as a double H profile wherein the cross section of the fluid channelis rectangular, and the profile of the support arm.includes outer enforcement ribs.

In the embodiment shown, the first to fourth leading edge high-lift devices.-.are configured as a leading-edge droop nose device.-., and the support arrangementis configured as a hinge arrangementfor the leading-edge droop noses wherein the support arms.-.are configured as hinge arms,.wherein a first endof the hinge arm,.has a first rotational jointto be rotatably connected to the structureof the wingand a second endof the hinge armhas a second rotational jointto be rotatably connected to a movable rounded front partof the wing.

The hinge arrangementfurther comprises a driving systemfor driving a rotation of the hinge arm,.around the first rotational joint. In the embodiment shown, the driving systemcomprises a drive armthat may be fixedly connected to a rotatable driving shaft. The free end of the drive armis connected via a link rodto the hinge arm.

While the first and second rotational joints,of most of the hinge arms(here the first to fifth support arms.-.) are conventional and in principle known from the conventional droop nose systems such as those of Airbus A350, the first and second rotational joints,at the ends,of the hinge arm.which also functions as a fluid conduit (here the sixth hinge arm.which forms the sixth support arm.) are configured such that pressurized fluid may be conducted through the rotational joints,.

A possible embodiment of such rotational joint,configured as fluid conduit is explained using the example of the first rotational jointshown in. The first rotational jointhas a circular tube sectionand a bearingfor rotatably supporting the circular tube section. The circular tube sectionextends transversal to the hinge arm., i.e., transversal to the longitudinal extension of the hinge arm. The circular tube sectionis fixed to the tubular profile of the hinge arm.so that the interiors thereof are in fluid communication, and pressurized fluid such as anti-ice fluidcan be conducted from an anti-ice fluid supply (e.g., the turbine) through the circular tube sectioninto the fluid channelof the hinge arm..

Similarly, the pressurized anti-ice fluidis conducted through the second rotational jointinto the fluid systemarranged in the droop nose devices.-., as indicated in.

Referring to, the hinge arrangementfurther includes a link armfor connecting a hinge arm linkage pointwith a droop nose linkage point. The hinge arm linkage pointis located at the hinge arm,.with distance to the rotation axis of the second rotational joint. The droop nose linkage pointis located at the rounded front partwith distance from the rotation axis of the second rotational joint. Hence, the orientation of this rounded front partduring movement of the hinge arm is controlled and set by via the link arm.

The configuration of the support arm.to function both for movable support of a high-lift device.and for feeding fluidto and/or from the high-lift device.has been explained using an example where the support arm.is a hinge arm.for a droop nose device.. This has the advantage that such hinge arm.has a fixed length, and it is easy to implement a fluid conduit just by choosing a tubular section for the hinge arm.. In further embodiments (not shown), the support arm.is a telescopic support arm for a slat wherein the fluid channel is formed within members of the telescopic support arm. In other embodiments (not shown) more than one of the support arms.-.is configured as a fluid conduit. This enables e.g., providing closed loop fluid systems with a fluid supply conduit and a fluid discharge conduit.

A support arrangement () for a leading-edge high lift device (.) has been described which comprises a support arm (.) for movably supporting the leading-edge high lift device (.) on a wing structure (). In order to improve the possibility to supply the leading-edge high lift device (.) with a fluid such as an anti-ice fluid (), for example pressurized hot air, the support arm (.) is configured as a fluid conduit for feeding fluid () to and/or from the leading-edge high lift device (.). According to preferred embodiments, the leading-edge high lift device (.) is configured as a droop nose device (.).

While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms “comprise” or “comprising” do not exclude other elements or steps, the terms “a” or “one” do not exclude a plural number, and the term “or” means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.